A blog discussing sensors and instrumentation. New products, new technologies, and interesting applications. Types of sensors and instruments discussed include: Analyzers, Color Sensors, Displacement Sensors, Flow Sensors, Industrial Weighing, Instrumentation (Data Acquisition), Load Cells & Instrument Hardware. Machine Controls, Pressure Gauges, Pressure Sensors, Sanitary Sensors, Strain Gages, and Temperature Sensors. Courtesy of AP Corp.
Load Cells: The Vital Component in Precision Weighing
Breathing New Life into Aging Machinery: Reconditioning and Modernizing Your Plastic Injection Molding and Extrusion Equipment
Reconditioning of plastic injection mold and extrusion machines is a process that involves restoring or upgrading the machine to improve its performance, efficiency, and lifespan. This process can include replacing worn-out or outdated components, updating control systems, and enhancing the overall functionality of the machine. Key elements to consider for reconditioning are control systems, HMI (Human-Machine Interface), pressure sensors, temperature sensors, and feed screws. Here's a list of items to consider when reconditioning these machines:
- Inspection and assessment: Begin by thoroughly examining the machine to identify worn-out or damaged components, as well as outdated control systems and sensors. This assessment will help you determine the necessary upgrades and replacements needed.
- Disassembly: Carefully disassemble the machine, taking note of the locations and orientations of each component for reassembly later. Clean each part to remove accumulated debris and contaminants.
- Control system replacement: Remove and replace the existing control system with a modern, programmable system that offers improved performance and efficiency. This new system should be compatible with existing hardware and allow for seamless integration with the machine.
- HMI upgrade: Replace the old HMI with a modern, user-friendly interface that simplifies machine operation, monitoring, and control. This new HMI should be compatible with the updated control system and provide enhanced visualization and data-logging capabilities.
- Pressure sensor replacement: Replace outdated or damaged pressure sensors with new, high-precision sensors calibrated appropriately and integrated with the control system, ensuring accurate pressure measurement and monitoring throughout the injection and extrusion process.
- Temperature sensor replacement: Install new temperature sensors that provide accurate and reliable measurements. These sensors should be compatible with the control system and HMI, allowing for real-time monitoring and control of temperature during the injection and extrusion process.
- Feed screw replacement: Inspect the feed screws for wear, damage, or reduced efficiency. Replace them with new, high-performance screws designed for optimal material mixing and flow. Ensure proper alignment and installation to minimize wear and improve overall machine performance.
- Lubrication and maintenance: Lubricate all moving parts and replace worn-out seals or gaskets. Perform routine maintenance tasks such as filter changes and cleaning to ensure the machine operates smoothly.
- Reassembly: Reassemble the machine, ensuring all components are correctly installed and aligned. Double-check connections and wiring to ensure proper communication between sensors, control systems, and the HMI.
- Testing and calibration: Power the machine on and conduct a series of tests to verify proper function and performance. Calibrate the control system, sensors, and HMI to ensure accurate readings and control.
With these core steps, you can successfully recondition a plastic injection mold or extrusion machine, ensuring it operates efficiently and reliably for years.
Stress Analysis With the Use of Strain Gages
When external loads are applied, stress analysis assesses the internal forces and stresses acting on a material or structure. Strain gages, widely used in this process, measure the deformation (or strain) that occurs when a material experiences stress. The following provides a detailed explanation of how to accomplish stress analysis using strain gages:
- Selecting strain gages: The first step involves choosing an appropriate strain gage for the specific application. Consider factors such as the type of strain (e.g., tensile, compressive, shear), the expected magnitude and direction of strain, temperature range, and material properties of the test specimen.
- Preparing the surface: Before attaching the strain gauge, clean and thoroughly prepare the test specimen's surface, using solvents, abrasives, or other cleaning methods to remove contaminants, ensuring proper strain gage adhesion to the surface.
- Installing strain gages: Bond the strain gage to the test specimen using a specialized adhesive. Align the gage carefully toward the expected stress, accurately positioning the gage grid (which contains the sensing elements) over the area of interest. Once the adhesive cures, the strain gage installation is complete.
- Wiring and instrumentation: Connect the strain gage to a data acquisition system using lead wires. This system usually includes a signal conditioner, which amplifies the small electrical output from the strain gage, and an analog-to-digital converter, converting the analog signal into digital data for further analysis.
- Calibrating: Calibrate the strain gage and data acquisition system before starting the stress analysis. Apply known loads or strains to the test specimen and record the corresponding output from the strain gage. Create a calibration curve relating the measured strain to the electrical output of the gage.
- Applying loads and collecting data: With the strain gage installed and calibrated, subject the test specimen to the desired external loads. As the sample deforms under load, the strain gage also deforms, causing a change in its electrical resistance. This change in resistance is proportional to the strain experienced by the material and can be measured and recorded by the data acquisition system.
- Analyzing data: Analyze the collected data to determine the stress experienced by the material. Typically, this involves comparing the measured strain to the material's known stress-strain relationship (e.g., elastic modulus). Depending on the complexity of the loading conditions, finite element analysis (FEA) or other computational methods may be employed to simulate the stress distribution within the specimen.
- Interpreting and concluding: Use the stress analysis results to evaluate the material's performance and assess the design's suitability for the intended application, including identifying potential failure points, assessing fatigue life, or optimizing the design to reduce stress concentrations.
In summary, stress analysis using strain gages requires selecting, installing, calibrating, applying external loads, collecting data, and analyzing the stress-strain data to understand the material's response to the applied loads.
The Role of Feed Screws in The Plastics Melt Stream Process
Feed screws, also known as extruder screws, play a crucial role in the melt stream process of the plastics industry. The melt stream process transforms raw plastic materials into a continuous, homogenized, and viscous molten mass, which can be further shaped and processed into various products like films, sheets, pipes, profiles, and more. The feed screw is an essential component of the extruder machine, the primary equipment used in the melt stream process.
The role of the feed screw in the melt stream process is explained in detail by understanding its different sections and their functions:
- Solid conveying (feed) zone: The feed screw consists of a helical channel or flights with a rotating shaft that runs along its length. The screw begins with a hopper where raw plastic material, usually pellets or granules, is loaded. The rotation of the screw transports the raw material forward, creating a solid conveying zone. The screw geometry in this zone efficiently moves the plastic material toward the subsequent zones.
- Compression (transition) zone: The depth of the screw channel decreases gradually in this zone, causing the plastic material to compress. This compression generates heat through friction, which melts the plastic along with external heating elements. At the same time, the screw design ensures proper mixing and homogenization of the plastic materials.
- Melting (metering) zone: This zone is characterized by a constant channel depth, where the plastic material becomes fully molten. The screw's geometry creates a uniform and consistent melt flow while providing sufficient back pressure to ensure the homogenization of the molten plastic. Additional mixing elements may be incorporated into the screw design to enhance mixing and homogenization further.
- Discharge (melt) zone: In this final zone, the screw conveys the molten plastic towards the extruder die, designed to shape the material into the desired product form. A screen pack and breaker plate are typically placed before the die to filter out contaminants and ensure a uniform melt flow.
Feed screws play a vital role in the overall efficiency and quality of the melt stream process. The design of the screw and its various geometries can significantly affect the processing conditions, output rate, and final product quality. Different types of feed screws are available, tailored to the specific requirements of the plastic materials and end products, such as single-screw, twin-screw, and multi-screw extruders. These screws may also be classified based on their compression ratio, screw profile, and mixing elements.
Micro-Epsilon Introduces scanCONTROL AIK Adapter for Cognex® VisionPro® 2D/3D Analysis Software
Induction Heating Systems and Solutions for Industry
Industrial induction heating systems are used for various purposes in manufacturing, like surface hardening, brazing, welding, melting, and forging, among others.
- Automotive industry - for engine parts' surface hardening and brazing fuel lines.
- Aerospace industry - for welding titanium components, heat treating blades and vanes, and brazing aluminum components.
- Metal fabrication industry - for forging, hardening, and welding of steel parts.
- Jewelry industry - for melting gold and silver alloys to make jewelry.
- Energy industry - for heating tubes and pipes in heat exchangers and boilers.
- Medical industry - for sterilizing medical instruments and welding stainless steel components.
- Electronic industry - for soldering and brazing of electronic components and assemblies.